Performance Evaluation of MAC Aware QOS Provisioned Hybrid Routing Over VANET

Abstract

A vehicular ad-hoc network adopts some attributes of MANET and provides communication between high speed vehicles. VANET based communication can be classified into three categories i.e. Vehicle to Vehicle (V2V), Vehicle to Infrastructure and Hybrid which combines both V2V and V2I schemes. VANET has the potential of achieving goals of intelligent transport system (ITS) increasing road safety and transport efficiency. VANET though being a sub-class of MANET has distinguishing features that make routing in VANET a baffling problem. Timely and accurate information dissemination is the primary concern. QoS guaranteed routing with minimum packet collisions will increase the efficiency and throughput of the channel. Back-off algorithms are used to reduce the number of collisions when nodes try to access the channel simultaneously. In this paper, we deployed a back-off method called Modified Back-off algorithm (MBA) in the MAC layer of IEEE 802.11p. The simulations are carried out using NS-2 in order to study the behavior of hybrid routing protocol, ZRP with two different back-off mechanisms utilized at the MAC layer. Evaluations are done using Nakagami propagation model with different vehicle densities and packet sizes. The performance is investigated in terms of throughput, packet delivery ratio, routing load and end to end delay.